The present invention relates to methods for producing chewing gum. More particularly the invention relates to producing chewing gum containing an effective amount of an active ingredient or ingredients, including a stimulant known as caffeine. The caffeine or other active ingredient that is added to the chewing gum has been treated to control its rate of release from chewing gum by adding the treated active agent to a gum coating.
In recent years, efforts have been devoted to controlling release characteristics of various ingredients in chewing gum. Most notably, attempts have been made to delay the release of sweeteners and flavors in various chewing gum formulations to thereby lengthen the satisfactory chewing time of the gum. Delaying the release of sweeteners and flavors can also avoid an undesirable overpowering burst of sweetness or flavor during the initial chewing period. On the other hand, some ingredients have been treated so as to increase their rate of release in chewing gum.
Besides sweeteners, other ingredients may require a controlled release from chewing gum. In certain embodiments, it is contemplated that the active agent that is added to the gum may be a stimulant such as caffeine. However, stimulants are not generally released very readily. An active stimulant such as caffeine may be encapsulated in a water soluble matrix such that, during the chewing period, the caffeine may be released quickly, resulting in a fast release of stimulant as in a beverage. This would allow chewing gum to be a carrier for an active agent such as caffeine and, with these fast release characteristics the gum may be used as an effective stimulant.
In some instances, serious taste problems may arise because of the bitter nature of many active agents. A prolonged or delayed release of an active agent(s) would allow for the use of the active agent(s) in gum, but the low level of release of such an agent may keep the level of that agent below the taste threshold of the active agent, and not give chewing gum a bitter taste quality. In addition, active agents may also have other unpleasant tastes that may be overcome by reducing the release rate of active agent from a chewing gum.
Another aspect of the present invention contemplates the use of encapsulation techniques. For example, it may be that active agents may also be unstable in a chewing gum environment. In such cases, various methods of encapsulation may be needed to improve stability of the active agent. In other circumstances, active agents may not be readily released from the chewing gum matrix and their effect may be considerably reduced. In such a situation, a fast release encapsulation may be needed to release active agent(s) from the gum matrix.
Other methods contemplated are method of controlling release of active agent(s) from gum. These methods would be useful in not releasing the active agent in the oral cavity during gum chewing, but allowing the active agent to be ingested during chewing. This will keep the active agent from becoming effective until after it enters the digestive track.
Thus, there are specific advantages to adding active agent(s) to chewing gum by controlled release mechanisms.
The use of caffeine in chewing gum is disclosed in U.S. Pat. No. 1,298,670. The controlled release of caffeine in chewing gum is disclosed in PCT Patent Publication No. WO 98/23165.
Chewing gum containing caffeine as a stimulant and to combat fatigue and migraine headaches is disclosed in French Patent No. 2 345 938 and in West Germany Patent No. 43 42 568.
Also, two Japanese Patent Publications, Nos. JP 1991-112450 and JP 1991-251533, disclose the use of caffeine in chewing gum to reduce drowsiness.
In Japanese Patent Publication No. JP 1996-019370, caffeine is added to chewing gum as an after meal chewing gum to replace tooth brushing.
Caffeine is a well known stimulant from coffee and tea, and several patents disclose the use of coffee or tea in gum, such as Japanese Patent Publication No. JP 1994-303911, South Korea Patent Publication No. 94-002868, and PCT Patent Publication No. WO 95/00038.
The present invention provides a method of producing chewing gum with physically modified active agents such as caffeine to control their release. Such active agents are added to a gum coating to deliver the active agents systemically without unpleasant tastes. The present invention also relates to the chewing gum so produced. Physically modified active agents such as caffeine may be added to sucrose-type gum formulations and sucrose-type coatings. The formulation may be a low or high moisture formulation containing low or high amounts of moisture containing syrup. Physically modified active agents such as caffeine may also be used in low or non-sugar gum formulations and coatings that use sorbitol, mannitol, other polyols or carbohydrates. Non-sugar formulations may include low or high moisture sugar-free chewing gums.
Active agents such as caffeine and the other active agents described herein may be combined or co-dried with bulk sweeteners typically used in chewing gum before the active agent(s) are physically modified. Such bulk sweeteners are sucrose, dextrose, fructose and maltodextrins, as well as sugar alcohols such as sorbitol, mannitol, xylitol, maltitol, lactitol, hydrogenated isomaltulose and hydrogenated starch hydrolyzates.
The modified release rate noted above may be a fast release or a delayed release. The modified release of active agents such as caffeine may be obtained by encapsulation, partial encapsulation or partial coating, entrapment or absorption with high or low water soluble materials or water insoluble materials. The procedures for modifying the active agent include spray drying, spray chilling, fluid bed coating, coacervation, extrusion and other agglomerating and standard encapsulating techniques. The active agents also may be absorbed onto an inert or water-insoluble material. Active agents may be modified in a multiple step process comprising any of the processes, or a combination of the processes noted. Prior to encapsulation, active agents may also be combined with bulk sweeteners including sucrose, dextrose, fructose, maltodextrin or other bulk sweeteners, as well as sugar alcohols such as sorbitol, mannitol, xylitol, maltitol, lactitol, hydrogenated isomaltulose and hydrogenated starch hydrolyzates.
Prior to encapsulation, active agents such as caffeine may be combined with high-intensity sweeteners, including but not limited to thaumatin, aspartame, alitame, acesulfame K, saccharin acid and its salts, glycyrrhizin, cyclamate and its salts, stevioside and dihydrochalcones. Co-encapsulation of active agents along with a high-intensity sweetener may reduce the poor taste qualities of active agents and control the sweetener release with active agents. This can improve the quality of the gum product and increase consumer acceptability.
Preferably, the physically modified active agents such as caffeine are mixed with a panning syrup and then applied as a chewing gum coating. The coating is applied by panning techniques that may use sugars for a sugar panned product or may use sorbitol, xylitol, or other polyols to make either a soft or hard shell sugarless panned product. By adding physically modified active agents to a gum coating, the active agents will not be available in the mouth for tasting, but carried with the carbohydrate used in the coating and ingested into the digestive system, where the active agents can be absorbed systemically for its effect. This technique significantly reduces the overall poor quality taste of active agents as it is masked by the encapsulant in the mouth during chewing, and results in a gum product having increased consumer acceptability.